It is a commonly used technology in modern industries to separate various phases from a mixture containing multiple phases, and the technology has been widely used in multiple fields. For example, in municipal sewage treatment and industrial sewage treatment, the sewage containing oil and suspended solids needs to be separated, so as to perform classified treatment afterwards.
In addition, in the oil extraction industry, it is even an important technology to perform phase separation on the oilfield produced liquid. The oilfield produced liquid is complex in components, but it can usually be deemed as a three-phase mixture which mainly contains three phases, including water, oil and suspended solids.
Traditional dewatering device takes controlling moisture content in the oil as its main function, focusing on dewatering from the oilfield produced liquid, and therefore can be used to treat the oilfield produced liquid with high moisture content. However, the traditional dewatering device has the shortcomings of high energy consumption, low efficiency, high content of oil in the discharged water, and complex sewage post-treatment process.
In the prior arts, a built-in member is further used to improve the efficiency and effect in separating oil, water and solids. For example, CN101766921A and CN103752042A respectively disclose a device for separating oil, water and solids, wherein in both patents, a wing-shaped plate component is used as a built-in member. After settlement and delamination, the crude oil produced liquid with an extremely high content of moisture enters the wing-shaped plate component, wherein the separation of oil, water and solids is realized through density differences. However, the oil content in the discharged water from such device for separating oil, water and solids is still greater than 500 mg/L, and only about 80% mud is separated out from the produced liquid, thereby requiring a very complex sewage post-treatment system. Therefore, such device for separating oil, water and solids cannot satisfy the requirements of oilfield produced liquid containing a high content of moisture on efficient treatment of a large amount of liquid.